Fresh fruit rapidly deteriorates particularly when the flesh of the fruit is exposed, such as by peeling the skin or by slicing the fruit. The appearance, flavor, texture, and crispness rapidly degrades. Within hours, fruit, such as apples, begins to turn brown and lose its distinctive flavor. The fruit loses its texture and hardness; the fruit becomes soft and loses its characteristic crispness.
Methods of preservation involve cooking which changes flavor and texture; typically appearance is also changed. Freezing substantially preserves flavor; however texture and crispness are affected. Furthermore, frozen foods need to be continually stored and require freezers for storage. Drying often preserves flavor but texture, crispness and appearance are substantially affected. Refrigeration helps to preserve crispness texture and flavor for a limited number of hours but does not prevent browning. Chemical preservatives are often used alone or in conjunction with these methods of preserving, however they typically leave a residual taste.
One method employs four active ingredients an acidulant such as citric acid, a metal sequesterant or chelant such as sodium acid polyphosphate, an enzyme inhibitor such as calcium chloride and an antioxidant such as ascorbic acid. However, the fruit has an unpleasant taste and the fruit typically turns brown within 5 days.
Citric acid, which is present in lemon juice, has been used to delay browning in fruits; however, the fruit tastes sour, becomes soft and soggy, and typically within hours the fruit turns brown.
Sodium ascorbate has also been used to preserve fruit; while the color degradation is delayed, the fruit has a noticeable taste.
Other methods often involve forming a film on the surface of the fruit; however such films often leave an unacceptable gummy feel when eaten.
It would be desirable to have a method for preserving fruit, particularly cut fruit, which preserves the appearance, color, texture crispness and flavor, yet does not leave an after taste nor require cooking, drying or freezing.